Are ventless fireplaces safe to use?

If you plan to use a ventless fireplace to save money, make sure you consider the safety concerns.

Some service providers say unvented fireplaces burn more efficiently than their vented gas-powered counterparts and cost less to install. Other providers and organizations contend that ventless fireplaces are unsafe or otherwise undesirable.

The National Association of Certified Home Inspectors warns that these fireplaces necessarily vent unburned combustion products — including carbon monoxide — directly into the living space. Although most vent free manufacturers install an oxygen-detection sensor designed to automatically shut the fireplace down if oxygen levels in the home become too low, a lot is riding on that sensor working. NACHI recommends having the unit inspected before use.

Health risks

While no deaths from vent free fireplace incidents have been reported, NACHI says, some municipalities have restricted or outlawed vent-free fireplaces. The District of Columbia bans the fireplaces in bedrooms and bathrooms, and California banned all ventless fireplaces because of the risks, but no other states outlaw their use.

“They put out tons of heat and they’re 100 percent efficient, but they use oxygen in the room and put out carbon monoxide, and they smell terrible,” says Bill Yeager, owner of Yeager Gas Fireplace Service in Fredericksburg, Va. “It’s like a car running in the house,” Yeager says. He says he had a ventless fireplace in his own home for five years and installs and services them, but he typically steers customers to other options.

Maintenance

On the other hand, Steve Swerdlin, owner of Steve the Fireplace Guy in Olney, Md., endorses ventless fireplaces. He says vent-free fireplaces that are properly installed and serviced annually should function well. “There’s a lot of training in this industry now, and once it’s serviced by someone who knows what they’re doing, you shouldn’t have problems,” Swerdlin says, but adds that he doesn’t recommend ventless fireplaces for people with respiratory issues, asthma or severe allergies.

Angela Tin, the American Lung Association’s vice president of environmental health, agrees. “Generally, we don’t recommend combustion products for people with health problems, but for healthy people, if the carbon monoxide sensors are working properly, they would seem to be fine,” she says.

Maintenance Tips

• Make sure logs are placed correctly, according to the instructions.

• Have your fireplace inspected annually.

• Make sure your fireplace sensor is free of dust and other particles.

Swerdlin says annual service and proper fireplace maintenance eliminate most dangers. He charges between $175 and $225 for the service, depending on how much cleaning the fireplace requires. Dust and other particles clog the sensor, which need to be cleaned once a year, he says. He adds that the logs need to be placed a certain way in the fireplace, which should come with a diagram. “If the logs aren’t in the right place, it can create black soot, and the logs will produce carbon monoxide,” Swerdlin says.

Real estate agents say vent-free fireplaces don’t affect a home’s resale value when compared to their vented counterparts, but they add that they’ll suggest a vented fireplace if a homeowner needs to choose between the two options. “Homeowners usually just see a fireplace, and don’t think much about how it operates,” says Dianne Hansen, a Realtor in Fairfax, Va. Either option provides a return on investment, says Brian Pakulla, a Realtor with RE/MAX Advantage in Columbia, Md. “Having a fireplace at all adds value.”

If your fireplace requires a gas-line connection, check with your state and/or municipality to see what the licensing requirements are. Some states require the installer to be licensed. Some contractors will install the gas lines, while others won’t, so homeowners should ask installers what they’re able to do and what their home will need for a vent-free installation. The National Fireplace Institute provides certifications for installers, including a gas specialist distinction for vent-free installers, but the certification isn’t required by law.

Costs

Yeager charges around $900 for a ventless fireplace installation that includes gas logs, which typically cost between $200 and $300 if purchased separately. Gas log sets for vented fireplaces cost $1,200 to $1,400.

Swerdlin says the fireplaces have improved over time and remain a convenient option. “There are no liners you have to deal with and no chimney issues,” he says. “(Low) cost and heat are the top reasons people want them.”